Google Earth Coordinates vs. GPS Device Coordinates

I'm a little confused about Google Earth's GPS coordinates vs. my Garmin Gek301's GPS coordinates. They seem to be using different formats.

According to the Garmin manual I should be using MAP Datum WGS 84 and position format H D(degrees)M.M' .

OK, but Google Earth says Degrees, Minutes and Seconds and uses a slightly different format if I edit a placemark and look at the latitude and longitude of a location.

All I'm trying to do at the moment is to pinpoint a location on Google Earth, go to geocaching.com and search for caches in that surrounding area by entering the Google coordinate into the "WGS84 Datum" search box.

Of course it would also be good to be able to mark caches I've found, know that I'm using the right format in my Garmin device for entry of the cache locations, etc. Can someone help? I've search and search but can't find the answer. Guess I am very dense!!

For some reason Google Earth uses DD MM SS.S (degrees, minutes, and seconds to one decimal) for coordinates. This was the traditional way of showing latitude and longitude, I remember it when I first learned of these two concepts in upper elementary school in the late 70's.

But in the last decade or so, using DD.DDDDD (just degrees and the decimal) or more so DD MM.MMM (Degrees and minutes to the 3rd decimal) are more common. The latter is the official geocaching coordinate method and is usually the default way that most GPSrs show coordinates (though a GPS I used to own, the Galileo by the Whistler radar detector people, ONLY showed coords the Google Earth way; and it seems one of the two GPSr I now have, the Lowrance IWay 100M, ONLY shows it the geocaching way).

Most GPSr's nowadays have the ability to show coordinates in any of the 3 formats, so you could manually enter a waypoint the way it's shown on Google Earth, then ask the GPS to show it as DD MM.MMM format

Most GPSr's nowadays have the ability to show coordinates in any of the 3 formats, so you could manually enter a waypoint the way it's shown on Google Earth, then ask the GPS to show it as DD MM.MMM format

Hope that helps!

The other way around is also true, you can setup google earth to show DD MM.MMM

The other way around is also true, you can setup google earth to show DD MM.MMM

How do I configure Google Earth to use DD MM.MMM?

Roy

Look for an Options... or Preferences... menu item (depends if you are using the PC or Mac version). There is an option in the "View" tab for Lat/Lon as "Degrees" which is "xx.xxxxxx", or "Degrees, Minutes, Seconds" which is "dd mm ss.ss".

I leave my gps in "dd mm.mmm" mode which is what geocaching.com uses. You can enter a location in that format directly into google earth in the fly to search box. When taking a location from google earth and searching on the gc.com site, you can select decimal degrees on the search page, and use the location given by google earth.

Make sure your GPS is set for WGS 84 datum, otherwise your locations will be off. Even though the gc.com page says "WGS 84" for entering locations in "dd mm.mmm" format and "decimal degrees" for entering locations in "dd.dddddd" format, they both use the WGS 84 datum. It's just they way they labeled the boxes.

The other way around is also true, you can setup google earth to show DD MM.MMM

How do I configure Google Earth to use DD MM.MMM?

Roy

Look for an Options... or Preferences... menu item (depends if you are using the PC or Mac version). There is an option in the "View" tab for Lat/Lon as "Degrees" which is "xx.xxxxxx", or "Degrees, Minutes, Seconds" which is "dd mm ss.ss".

I leave my gps in "dd mm.mmm" mode which is what geocaching.com uses. You can enter a location in that format directly into google earth in the fly to search box. When taking a location from google earth and searching on the gc.com site, you can select decimal degrees on the search page, and use the location given by google earth.

Make sure your GPS is set for WGS 84 datum, otherwise your locations will be off. Even though the gc.com page says "WGS 84" for entering locations in "dd mm.mmm" format and "decimal degrees" for entering locations in "dd.dddddd" format, they both use the WGS 84 datum. It's just they way they labeled the boxes.

OK, think I've got it. Would appreciate confirmation from those in the know.

Google Earth on my Mac:
Set preferences to "Degrees, Minutes, Seconds". This looks to be the default.
Place marks show latitude - 41()41'52.60"N, longitude - 88() 8'13.70"W

Garmin geko 301:
Position format choices are - H D.D(), H D()M.M' and H D()M'S.S"
Looks like H D()M'S.S" is the correct choice? This is NOT the default.

Using the above, the Google Earth map location was pretty close to where I stopped my car on the way out of the dog park yesterday and marked the location in my Geko. It's probably within 15 feet.

Using my home as an example, I marked my spot on the sidewalk but Google Earth put me the edge of the street. Again probably within 15 feet and I think the accuracy may have been 16 feet. I need to do some more testing but does the Geko position format choice seem correct??

So how would I enter the park location in the WGS84 Datum latitude longitude search boxes on geocaching.com?

No, all that google earth does is make you write the coordinates with an apostrophe, a quotation mark and a space before you put the hemisphere symbol (like W or S) when you set the coordinate system to DMS. Just type it in like this:
00 00'00.00" N, 00 00'00.00" W
You can also insert the degrees sign after the first set of digits if you want to. On geocaching.com, enter the coordinates as shown above the coordinate entry box.

You can paste any of the above coordinates into google earth and it will read them. GC.com can search by the two formats listed on the search page. As long as you are all speaking the same datum (which google earth and gc.com are, and you've set your GPS to use WGS 84) then any of the above formats would work.

As for the 15 foot accuracy, that's pretty good. The best you may see is around 7 feet with WAAS enabled on your GPS.

I'm a little confused about Google Earth's GPS coordinates vs. my Garmin Gek301's GPS coordinates. They seem to be using different formats.

According to the Garmin manual I should be using MAP Datum WGS 84 and position format H D(degrees)M.M' .

OK, but Google Earth says Degrees, Minutes and Seconds and uses a slightly different format if I edit a placemark and look at the latitude and longitude of a location.

All I'm trying to do at the moment is to pinpoint a location on Google Earth, go to geocaching.com and search for caches in that surrounding area by entering the Google coordinate into the "WGS84 Datum" search box.

Of course it would also be good to be able to mark caches I've found, know that I'm using the right format in my Garmin device for entry of the cache locations, etc. Can someone help? I've search and search but can't find the answer. Guess I am very dense!!

Thanks!

Entering and displaying are separate on Google Earth. It is pretty smart at figuring out what you entered. There are 60 minutes in a degree so 57.5 degress equals 57 degrees 30 minutes. If you enter two numbers GE guesses degrees and minutes. 60 seconds in a minute so three numbers are DMS. Also, You can drop loc or gpx files on GE:

I guess I should have posed my question differently. What I meant was, is it possible to configure Google Earth so that when I put the pointer a certain place, it will return the latitude and Longitude in DD MM.MMM, so t hat I don't have to convert it before entering it into my GPS?

In Tools, Options, Show Lat/Long I see options of Degrees, Minutes, seconds,
or Degrees
or UTM